Spin injection, spin transport and controllable ferromagnetism in transition metal doped ZnO

电子和空穴自旋在未来半导体器件中的应用是当前研究的焦点。自旋电子学和自旋光电子学的新器件概念的发展的关键先决条件是实现自旋极化电荷载流子的有效注入，以及对自旋自由度的传输，操纵和检测的透彻理解。本提案旨在研究氧化锌基材料系统和调查的自旋相关的性质，使用电气和光学技术。ZnO基材料系统是特别有前途的，因为ZnO可以与半金属铁磁氧化物集成在全氧化物外延异质结构中。该项目的主要目标包括：（i）制备外延ZnO薄膜和异质结构以及适合自旋（光）电子器件需要的[ZnO/铁磁]n数字合金，（ii）通过光泵浦和探测实验研究ZnO中的自旋寿命和自旋相干长度，（iii）铁磁/ZnO异质结构中的电自旋注入和自旋输运的光学研究，（iv）高质量外延ZnO薄膜的全电自旋注入和自旋输运研究。

The use of electron and hole spins for future semiconductor devices is in the focus of current research. Key prerequisites for the development of novel device concepts for spin electronics and spin optoelectronics are the realization of an effective injection of spin-polarized charge carriers, as well as the thorough understanding of the transport, manipulation and detection of the spin degree of freedom. The present proposal aims at the study of ZnO-based material systems and the investigation of their spin related properties using electrical and optical techniques. ZnO-based material systems are particularly promising as ZnO can be integrated with half-metallic ferromagnetic oxides in all-oxide epitaxial heterostructures. The key objectives this project include (i) the fabrication of epitaxial ZnO thin films and heterostructures as well as [ZnO/ferromagnet]n digital alloys tailored to the needs of spin (opto)electronic devices, (ii) the study of the spin lifetime and spin coherence length in ZnO by optical pump & probe experiments, (iii) the optical study of electrical spin injection and spin transport in ferromagnet/ZnO heterostructures, and (iv) the investigation of all-electrical spin injection and spin transport in high quality epitaxial ZnO thin films.